Henry Spencer is a Canadian computer programmer and space enthusiast. He wrote 'regex', a widely-used software library for regular expressions, and co-wrote C News, a Usenet server program. He also authored The Ten Commandments for C Programmers. He is coauthor, with David Lawrence, of the book Managing Usenet . While working at the University of Toronto he ran the first active Usenet site outside the US, starting in 1981. His records from that period were eventually acquired by Google to provide an archive of Usenet in the 1980s